Vulnerability-Lookup

GHSA-FCV2-XGW5-PQXF

Vulnerability from github – Published: 2026-01-22 20:28 – Updated: 2026-01-23 15:49

Summary

sigstore legacy TUF client allows for arbitrary file writes with target cache path traversal

Details

Summary

The legacy TUF client pkg/tuf/client.go, which supports caching target files to disk, constructs a filesystem path by joining a cache base directory with a target name sourced from signed target metadata, but it does not validate that the resulting path stays within the cache base directory.

Note that this should only affect clients that are directly using the TUF client in sigstore/sigstore or are using an older version of Cosign. As this TUF client implementation is deprecated, users should migrate to https://github.com/sigstore/sigstore-go/tree/main/pkg/tuf as soon as possible.

Note that this does not affect users of the public Sigstore deployment, where TUF metadata is validated by a quorum of trusted collaborators.

Impact

A malicious TUF repository can trigger arbitrary file overwriting, limited to the permissions that the calling process has.

Workarounds

Users can disable disk caching for the legacy client by setting SIGSTORE_NO_CACHE=true in the environment, migrate to https://github.com/sigstore/sigstore-go/tree/main/pkg/tuf, or upgrade to the latest sigstore/sigstore release.

Severity ?

5.8 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:N/I:H/A:N

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JSON

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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.10.3"
      },
      "package": {
        "ecosystem": "Go",
        "name": "github.com/sigstore/sigstore"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.10.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-24137"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-22"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-22T20:28:56Z",
    "nvd_published_at": "2026-01-23T00:15:52Z",
    "severity": "MODERATE"
  },
  "details": "## Summary\n\nThe legacy TUF client `pkg/tuf/client.go`, which supports caching target files to disk, constructs a filesystem path by joining a cache base directory with a target name sourced from signed target metadata, but it does not validate that the resulting path stays within the cache base directory.\n\nNote that this should only affect clients that are directly using the TUF client in sigstore/sigstore or are using an older version of Cosign. As this TUF client implementation is deprecated, users should migrate to https://github.com/sigstore/sigstore-go/tree/main/pkg/tuf as soon as possible.\n\nNote that this does not affect users of the public Sigstore deployment, where TUF metadata is validated by a quorum of trusted collaborators. \n\n## Impact\n\nA malicious TUF repository can trigger arbitrary file overwriting, limited to the permissions that the calling process has.\n\n## Workarounds\n\nUsers can disable disk caching for the legacy client by setting `SIGSTORE_NO_CACHE=true` in the environment, migrate to https://github.com/sigstore/sigstore-go/tree/main/pkg/tuf, or upgrade to the latest sigstore/sigstore release.",
  "id": "GHSA-fcv2-xgw5-pqxf",
  "modified": "2026-01-23T15:49:39Z",
  "published": "2026-01-22T20:28:56Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/sigstore/sigstore/security/advisories/GHSA-fcv2-xgw5-pqxf"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-24137"
    },
    {
      "type": "WEB",
      "url": "https://github.com/sigstore/sigstore/commit/8ec410a2993ea78083aecf0e473a85453039496e"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/sigstore/sigstore"
    },
    {
      "type": "WEB",
      "url": "https://github.com/sigstore/sigstore/releases/tag/v1.10.4"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "sigstore legacy TUF client allows for arbitrary file writes with target cache path traversal"
}

CVE-2026-24137 (GCVE-0-2026-24137)

Vulnerability from cvelistv5 – Published: 2026-01-23 00:04 – Updated: 2026-01-23 19:55

Title

sigstore legacy TUF client allows for arbitrary file writes with target cache path traversal

Summary

sigstore framework is a common go library shared across sigstore services and clients. In versions 1.10.3 and below, the legacy TUF client (pkg/tuf/client.go) supports caching target files to disk. It constructs a filesystem path by joining a cache base directory with a target name sourced from signed target metadata; however, it does not validate that the resulting path stays within the cache base directory. A malicious TUF repository can trigger arbitrary file overwriting, limited to the permissions that the calling process has. Note that this should only affect clients that are directly using the TUF client in sigstore/sigstore or are using an older version of Cosign. Public Sigstore deployment users are unaffected, as TUF metadata is validated by a quorum of trusted collaborators. This issue has been fixed in version 1.10.4. As a workaround, users can disable disk caching for the legacy client by setting SIGSTORE_NO_CACHE=true in the environment, migrate to https://github.com/sigstore/sigstore-go/tree/main/pkg/tuf, or upgrade to the latest sigstore/sigstore release.

Severity ?

5.8 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:N/I:H/A:N

CWE

CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Assigner

GitHub_M

References

URL

Tags

	https://github.com/sigstore/sigstore/security/adv…	x_refsource_CONFIRM
	https://github.com/sigstore/sigstore/commit/8ec41…	x_refsource_MISC
	https://github.com/sigstore/sigstore/releases/tag…	x_refsource_MISC

Impacted products

	Vendor	Product	Version
	sigstore	sigstore	Affected: < 1.10.4

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-24137",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-23T19:55:31.439546Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-01-23T19:55:42.582Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "sigstore",
          "vendor": "sigstore",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.10.4"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "sigstore framework is a common go library shared across sigstore services and clients. In versions 1.10.3 and below, the legacy TUF client (pkg/tuf/client.go) supports caching target files to disk. It constructs a filesystem path by joining a cache base directory with a target name sourced from signed target metadata; however, it does not validate that the resulting path stays within the cache base directory. A malicious TUF repository can trigger arbitrary file overwriting, limited to the permissions that the calling process has. Note that this should only affect clients that are directly using the TUF client in sigstore/sigstore or are using an older version of Cosign. Public Sigstore deployment users are unaffected, as TUF metadata is validated by a quorum of trusted collaborators. This issue has been fixed in version 1.10.4. As a workaround, users can disable disk caching for the legacy client by setting SIGSTORE_NO_CACHE=true in the environment, migrate to https://github.com/sigstore/sigstore-go/tree/main/pkg/tuf, or upgrade to the latest sigstore/sigstore release."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.8,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "HIGH",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:N/I:H/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-22",
              "description": "CWE-22: Improper Limitation of a Pathname to a Restricted Directory (\u0027Path Traversal\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-01-23T00:04:19.046Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/sigstore/sigstore/security/advisories/GHSA-fcv2-xgw5-pqxf",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/sigstore/sigstore/security/advisories/GHSA-fcv2-xgw5-pqxf"
        },
        {
          "name": "https://github.com/sigstore/sigstore/commit/8ec410a2993ea78083aecf0e473a85453039496e",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/sigstore/sigstore/commit/8ec410a2993ea78083aecf0e473a85453039496e"
        },
        {
          "name": "https://github.com/sigstore/sigstore/releases/tag/v1.10.4",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/sigstore/sigstore/releases/tag/v1.10.4"
        }
      ],
      "source": {
        "advisory": "GHSA-fcv2-xgw5-pqxf",
        "discovery": "UNKNOWN"
      },
      "title": "sigstore legacy TUF client allows for arbitrary file writes with target cache path traversal"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-24137",
    "datePublished": "2026-01-23T00:04:19.046Z",
    "dateReserved": "2026-01-21T18:38:22.474Z",
    "dateUpdated": "2026-01-23T19:55:42.582Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-FCV2-XGW5-PQXF

Summary

Impact

Workarounds

CVE-2026-24137 (GCVE-0-2026-24137)

Tags

Sightings

Nomenclature